You can't (easily) run the EQEmu server on Mac OS X. Though since they started using Intel processors it is possible at least if you have a bit of coding knowledge and time.
As for the Titanium client, you can use Crossover to get it to run, provided you have an Intel processor follow the tutorial here:
http://www.projecteq.net/phpBB2/viewtopic.php?t=4947
Of course, you could always dual boot Windows and Mac OS and run EQ natively on the Windows partition, but using Crossover is easier and less intrusive.